Doxorubicin-loaded Polymeric Biotin-PEG-SeSe-PBLA Micelles with surface Binding of Biotin-Mediated Cancer Cell Targeting and Redox-Responsive Drug release for enhanced anticancer efficacy.

Biotin receptors are overexpressed in various cancer cell types, essential in tumor development, metabolism, and metastasis. Chemotherapeutic agents may be more effective and have fewer adverse effects if they specifically target the biotin receptors on cancer cells. Polymeric micelles (PMs) with nanoscale size via the EPR effect to accumulate near tumor tissue. We utilized the solvent exchange technique to crate polymeric Biotin-PEG-SeSe-PBLA micelles. This underwent self-assembly to create uniformly dispersed PMs with a hydrodynamic diameter of 81.54 ± 0.23 nm. The resulting PMs characterized by 1HNMR, 13CNMR, FTIR, and Raman spectroscopy. PMs exhibited a high efficacy of Doxorubicin encapsulation (EE) and loading content (DLC), with values of 5.93 wt% and 74.32 %, respectively. DOX@Biotin-PEG-SeSe-PBLA micelles showed optimal DOX release, around 89 % and 74 % in 10 mM glutathione and 0.1 % H2O2, respectively, within 72 hours, in the simulated cancer redox pool. Fascinatingly, the blank Biotin-PEG-SeSe-PBLA micelles did not affect the HaCaT or HeLa cell lines; approximately 85 % of the cells were metabolically active. Contrarily, at a 5 µg/ml concentration, DOX@Biotin-PEG-SeSe-PBLA specifically inhibited the proliferation of roughly 76 % of HeLa cells and 11 % of HaCaT cells. The fluorescence microscopy results demonstrated that biotin-decorated micelles were more successfully internalized by HeLa cells, which overexpress the biotin receptor, than by non-targeted micelles in vitro. In summary, the diselenide-linked Biotin-PEGSeSe-PBLA formed smart PMs that could offer DOX specific to cancer cells with precision and are physiologically durable.

An Eco-Friendly Manner to Prepare Superwetting Melamine Sponges with Switchable Wettability for the Separation of Oil/Water Mixtures and Emulsions.

Oil/water separation processes have garnered significant global attention due to the quick growth in industrial development, recurring chemical leakages, and oil spills. Hence, there is a significant demand for the development of inexpensive superwetting materials in an eco-friendly manner to separate oil/water mixtures and emulsions. In this study, a superwetting melamine sponge (SMS) with switchable wettabilities was prepared by modifying melamine sponge (MS) with sodium dodecanoate. The as-prepared SMS exhibited superhydrophobicity, superoleophilicity, underwater superoleophobicity, and underoil superhydrophobicity. The SMS can be utilized in treating both light and heavy oil/water mixtures through the prewetting process. It demonstrated fast permeation fluxes (reaching 108,600 L m-2 h-1 for a light oil/water mixture and 147,700 L m-2 h-1 for a heavy oil/water mixture) and exhibited good separation efficiency (exceeding 99.56%). The compressed SMS was employed in separating surfactant-stabilized water-in-oil emulsions (SWOEs), as well as surfactant-stabilized oil-in-water emulsions (SOWEs), giving high permeation fluxes (reaching 7210 and 5054 L m-2 h-1, respectively). The oil purity for SWOEs' filtrates surpassed 99.98 wt% and the separation efficiencies of SOWEs exceeded 98.84%. Owing to their remarkable capability for separating oil/water mixtures and emulsions, eco-friendly fabrication method, and feasibility for large-scale production, our SMS has a promising potential for practical applications.

Mucin-mediated mucosal retention via end-terminal modified Pluronic F127-based hydrogel to increase drug accumulation in the lungs.

Noninvasive lung drug delivery is critical for treating respiratory diseases. Pluronic-based copolymers have been used as multifunctional materials for medical and biological applications. However, the Pluronic F127-based hydrogel is rapidly degraded, adversely affecting the mechanical stability for prolonged drug release. Therefore, this study designed two thermosensitive copolymers by modifying the Pluronic F127 terminal groups with carboxyl (ADF127) or amine groups (EDF127) to improve the viscosity and storage modulus of drug formulations. ß-alanine and ethylenediamine were conjugated at the terminal of Pluronic F127 using a two-step acetylation process, and the final copolymers were characterized using 1H nuclear magnetic resonance (1H NMR) and Fourier-transform infrared spectra. According to the 1H NMR spectra, Pluronic F127 was functionalized to form ADF127 and EDF127 with 85 % and 71 % functionalization degrees, respectively. Rheological studies revealed that the ADF127 (15 wt%) and EDF127 (15 wt%) viscosities increased from 1480 Pa.s (Pluronic F127) to 1700 Pa.s and 1800 Pa.s, respectively. Furthermore, the elastic modulus of ADF127 and EDF127 increased, compared with that of native Pluronic F127 with the addition of 5 % mucin, particularly for ADF127, thereby signifying the stronger adhesive nature of ADF127 and EDF127 with mucin. Additionally, ADF127 and EDF127 exhibited a decreased gelation temperature, decreasing from 33 °C (Pluronic F127 at 15 wt%) to 24 °C. Notably, the in vitro ADF127 and EDF127 drug release was prolonged (95 %; 48 h) by the hydrogel encapsulation of the liposome-Bdph combined with mucin, and the intermolecular hydrogen bonding between the mucin and the hydrogel increased the retention time and stiffness of the hydrogels. Furthermore, ADF127 and EDF127 incubated with NIH-3T3 cells exhibited biocompatibility within 2 mg/mL, compared with Pluronic F127. The nasal administration method was used to examine the biodistribution of the modified hydrogel carrying liposomes or exosomes with fluorescence using the IVIS system. Drug accumulation in the lungs decreased in the following order: ADF127 > EDF127 > liposomes or exosomes alone. These results indicated that the carboxyl group-modified Pluronic F127 enabled well-distributed drug accumulation in the lungs, which is beneficial for intranasal administration routes in treating diseases such as lung fibrosis.

Formation of Porous Structures and Crystalline Phases in Poly(vinylidene fluoride) Membranes Prepared with Nonsolvent-Induced Phase Separation-Roles of Solvent Polarity.

PVDF membranes were prepared with nonsolvent-induced phase separation, using solvents with various dipole moments, including HMPA, NMP, DMAc and TEP. Both the fraction of the polar crystalline phase and the water permeability of the prepared membrane increased monotonously with an increasing solvent dipole moment. FTIR/ATR analyses were conducted at the surfaces of the cast films during membrane formation to provide information on if the solvents were present as the PVDF crystallized. The results reveal that, with HMPA, NMP or DMAc being used to dissolve PVDF, a solvent with a higher dipole moment resulted in a lower solvent removal rate from the cast film, because the viscosity of the casting solution was higher. The lower solvent removal rate allowed a higher solvent concentration on the surface of the cast film, leading to a more porous surface and longer solvent-governed crystallization. Because of its low polarity, TEP induced non-polar crystals and had a low affinity for water, accounting for the low water permeability and the low fraction of polar crystals with TEP as the solvent. The results provide insight into how the membrane structure on a molecular scale (related to the crystalline phase) and nanoscale (related to water permeability) was related to and influenced by solvent polarity and its removal rate during membrane formation.

A CO2-Responsive Imidazole-Functionalized Fluorescent Material Mediates Cancer Chemotherapy.

We present a breakthrough in the synthesis and development of functional gas-responsive materials as highly potent anticancer agents suitable for applications in cancer treatment. Herein, we successfully synthesised a stimuli-responsive multifunctional material (I-R6G) consisting of a carbon dioxide (CO2)-sensitive imidazole moiety and spirolactam-containing conjugated rhodamine 6G (R6G) molecule. The resulting I-R6G is highly hydrophobic and non- or weakly fluorescent. Simple CO2 bubbling treatment induces hydrophobic I-R6G to completely dissolve in water and subsequently form self-assembled nanoparticles, which exhibit unique optical absorption and fluorescence behaviours in water and extremely low haemolytic ability against sheep red blood cells. Reversibility testing indicated that I-R6G undergoes reversible CO2/nitrogen (N2)-dependent stimulation in water, as its structural and physical properties can be reversibly and stably switched by alternating cycles of CO2 and N2 bubbling. Importantly, in vitro cellular assays clearly demonstrated that the CO2-protonated imidazole moiety promotes rapid internalisation of CO2-treated I-R6G into cancer cells, which subsequently induces massive levels of necrotic cell death. In contrast, CO2-treated I-R6G was not internalised and did not affect the viability of normal cells. Therefore, this newly created system may provide an innovative and efficient route to remarkably improve the selectivity, safety and efficacy of cancer treatment.

Photoreactive Mercury-Containing Metallosupramolecular Nanoparticles with Tailorable Properties That Promote Enhanced Cellular Uptake for Effective Cancer Chemotherapy.

A new potential route to enhance the efficiency of supramolecular polymers for cancer chemotherapy was successfully demonstrated by employing a photosensitive metallosupramolecular polymer (Hg-BU-PPG) containing an oligomeric poly(propylene glycol) backbone and highly sensitive pH-responsive uracil-mercury-uracil (U-Hg-U) bridges. This route holds great promise as a multifunctional bioactive nano-object for development of more efficient and safer cancer chemotherapy. Owing to the formation of uracil photodimers induced by ultraviolet irradiation, Hg-BU-PPG can form a photo-cross-linked structure and spontaneously forms spherical nanoparticles in aqueous solution. The irradiated nanoparticles possess many unique characteristics, such as unique fluorescence behavior, highly sensitive pH-responsiveness, and intriguing phase transition behavior in aqueous solution as well as high structural stability and antihemolytic activity in biological media. More importantly, a series of cellular studies clearly confirmed that the U-Hg-U photo-cross-links in the irradiated nanoparticles substantially enhance their selective cellular uptake by cancer cells via macropinocytosis and the mercury-loaded nanoparticles subsequently induce higher levels of cytotoxicity in cancer cells (compared to non-irradiated nanoparticles), without harming normal cells. These results are mainly attributed to cancer cell microenvironment-triggered release of mercury ions from disassembled nanoparticles, which rapidly induce massive levels of apoptosis in cancer cells. Overall, the pH-sensitive U-Hg-U photo-cross-links within this newly discovered supramolecular system are an indispensable factor that offers a potential path to remarkably enhance the selective therapeutic effects of functional nanoparticles toward cancer cells.

Fabrication and characterization of hybrid eco-friendly high methoxyl pectin/gelatin/TiO2/curcumin (PGTC) nanocomposite biofilms for salmon fillet packaging.

Hybrid eco-friendly nanocomposite films were fabricated by blending high-methoxyl pectin, gelatin, TiO2, and curcumin through the solution casting method. Various concentrations (0-5 wt%) of TiO2 nanoparticles (TNPs) and curcumin as an organic filler were added to the blend solutions. A high TNP concentration affected the surface morphology, roughness, and compactness of the films. Additionally, 3D mapping revealed the nanoparticle distribution in the film layers. Moisture content, water solubility, and light transmittance reduced dramatically with increasing TNP content, in accordance with the water vapor and oxygen permeabilities. X-ray diffraction revealed that the films were semicrystalline nanocomposites, and the thermal properties of the films increased when 5 wt% of TNPs was incorporated into the blend solution. Fourier-transform infrared and Raman analyses revealed interactions among biopolymers, nanoparticles, and organic fillers through hydrogen bonding. The shelf life of fresh salmon fillets was prolonged to six days for all groups, revealed by total viable counts and psychrotrophic bacteria counts, and the pH of the salmon fillets could be extended until the sixth day for all groups. Biodegradation assays demonstrated a significant weight loss in the nanocomposite films. Therefore, a nanocomposite film with 5 wt% TNPs could potentially be cytotoxic to NIH 3T3 cells.

Antiblood Cell Adhesion of Mussel-Inspired Chondroitin Sulfate- and Caffeic Acid-Modified Polycarbonate Membranes.

We fabricated a mussel-inspired hemocompatible polycarbonate membrane (PC) modified by the cross-linking of chondroitin sulfate and caffeic acid polymer using CA-CS via a Schiff base and Michael addition reaction and named it CA-CS-PC. The as-fabricated CA-CS-PC membrane shows excellent hydrophilicity with a water contact angle of 0° and a negative surface charge with a zeta potential of -32 mV. The antiadhesion property of the CA-CS-modified PC membrane was investigated by enzyme-linked immunosorbent assay (ELISA), using human plasma protein fibrinogen adsorption studies, and proved to have excellent antiadhesion properties, because of the lower fibrinogen adsorption. In addition, the CA-CS-PC membrane also shows enhanced hemocompatibility. Finally, blood cell attachment tests of the CA-CS-PC membrane were observed by CLSM and SEM, and the obtained results proved that CA-CS-PC effectively resisted cell adhesion, such as platelets and leucocytes. Therefore, this work disclosed a new way to design a simple and versatile modification of the membrane surface by caffeic acid and chondroitin sulfate and apply it for cell adhesion.

Sustainable, biocompatible, and mass-producible superwetting water caltrop shell biochars for emulsion separations.

The separation of oily wastewater, specifically emulsions, is a crucial global issue. Possible strategies for the efficient separation of emulsified oil/water mixtures through sustainable and environmentally friendly materials have recently drawn considerable attention. In our study, we prepared superwetting water caltrop shell biochar (WCSB) via a top-lit-updraft carbonization procedure. The as-prepared WCSB was characterized by superhydrophilicity, underwater superoleophobicity, underoil superhydrophilicity, and underoil water adsorption ability. Because of its superwetting properties, WCSB was used for the separation of both surfactant-stabilized oil-in-water emulsions (SOIWEs) and surfactant-stabilized water-in-oil emulsions (SWIOEs) with very high fluxes (up to 74,700 and 241,000 L m-2 h-1 bar-1 for SOIWE and SWIOE, respectively). The separation performances were excellent, with oil contents in all SOIWE filtrates lower than 10 ppm and oil purities in all SWIOE filtrates higher than 99.99 wt%. Moreover, WCSB was applied to separate dye-spiked emulsions. Due to their high emulsion separation ability, sustainability, good biocompatibility, and ease of mass production, the as-prepared WCSBs have notable potential for utilitarian applications.

PAMAM Dendritic Nanoparticle-Incorporated Hydrogel to Enhance the Immunogenic Cell Death and Immune Response of Immunochemotherapy.

The efficiency of chemotherapy is frequently affected by its multidrug resistance, immune suppression, and severe side effects. Its combination with immunotherapy to reverse immune suppression and enhance immunogenic cell death (ICD) has emerged as a new strategy to overcome the aforementioned issues. Herein, we construct a pH-responsive PAMAM dendritic nanocarrier-incorporated hydrogel for the co-delivery of immunochemotherapeutic drugs. The stepwise conjugation of moieties and drug load was confirmed by various techniques. In vitro experimental results demonstrated that PAMAM dendritic nanoparticles loaded with a combination of drugs exhibited spherical nanosized particles, facilitated the sustained release of drugs, enhanced cellular uptake, mitigated cell viability, and induced apoptosis. The incorporation of PAB-DOX/IND nanoparticles into thermosensitive hydrogels also revealed the formation of a gel state at a physiological temperature and further a robust sustained release of drugs at the tumor microenvironment. Local injection of this formulation into HeLa cell-grafted mice significantly suppressed tumor growth, induced immunogenic cell death-associated cytokines, reduced cancer cell proliferation, and triggered a CD8+ T-cell-mediated immune response without obvious systemic toxicity, which indicates a synergistic ICD effect and reverse of immunosuppression. Hence, the localized delivery of immunochemotherapeutic drugs by a PAMAM dendritic nanoparticle-incorporated hydrogel could provide a promising strategy to enhance antitumor activity in cancer therapy.

Protein-assisted biomimetic synthesis of nanoscale gadolinium-integrated polypyrrole for synergetic and ultrasensitive electrochemical assays of nicardipine in biological samples.

Electrically conductive polymer nanomaterials signify a promising class of sensing platforms in the field of electrochemistry, but their applications as electrocatalysts are commonly limited by their poor colloidal stability in aqueous media and large particle sizes. Inspired by biomineralization approaches for integrating nanoscale materials, herein, a gadolinium (Gd)-integrated polypyrrole (PPy) electrocatalyst (namely, BSA@PPy-Gd) was successfully prepared by choosing bovine serum albumin (BSA) as a stabilizer for biomimetic mineralization and polymerization in a "one-step" manner. BSA@PPy-Gd possesses outstanding water dispersibility, nanoscale morphology, and improved electrical conductivity. The electrocatalytic competency of the electrochemical (EC) sensing platform fabricated for the sensitive detection of nicardipine (NCD) was assessed. The synergy of remarkable conductivity, superior active surface area, and electrostatic interactions stimulated by the combination of BSA with the NH group of PPy on BSA@PPy-Gd and Gd increases the fast electron transfer at the analyte-electrode junction. The fabricated EC sensor, BSA@PPy-Gd/glassy carbon electrode (GCE), exhibits a current intensity greater than that of PPy/GCE, BSA/GCE, and bare GCE in terms of peak height at a pH of 7.0 in phosphate buffer solution. The newly fabricated EC sensing platform shows excellent electrocatalytic activities for the electroreduction of NCD in terms of a low detection limit (2 nM), good sensitivity, linear dynamic detection ranges (0.01-575 µM), operational stability, and repeatability and was also tested on rat and human serum specimens.

Combination of ovalbumin-coated iron oxide nanoparticles and poly(amidoamine) dendrimer-cisplatin nanocomplex for enhanced anticancer efficacy.

Enhancement of drug efficacy is essential in cancer treatment. The immune stimulator ovalbumin (Ova)-coated citric acid (AC-)-stabilized iron oxide nanoparticles (AC-IO-Ova NPs) and enhanced permeability and retention (EPR)-based tumor targeted 4.5 generation poly(amidoamine) dendrimer(4.5GDP)-cisplatin (Cis-pt) nanocomplex (NC) (4.5GDP-Cis-pt NC) were used for enhanced anticancer efficiency. The formations of 4.5GDP-Cis-pt NC, AC-IO, and AC-IO-Ova NPs were examined via FTIR spectroscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. The conjugation of Cis-pt with 4.5GDP was confirmed using carbon NMR spectroscopy. The tumor-specific 4.5GDP-Cis-pt NC provided 45%and 28% cumulative cisplatin release in 72 h at pH 6.5 and 7.4, respectively. A significant immune response with high TNF-α and IL-6 cytokine secretion was confirmed for the co-incubation of AC-IO-Ova with RAW 264.7 or HaCaT cells. AC-IO-Ova NPs were biocompatible with different cell lines, even at a high concentration (200 µg mL-1). However, AC-IO-Ova NPs mixed with 4.5GDP-Cis-pt NC (Cis-pt at 15 µg mL-1) significantly increased the cytotoxicity against the cancer cells in a dose-dependent manner with the increasing AC-IO-Ova NPs concentrations. The increased anticancer effects may be attributed to the generation of reactive oxygen species (ROS). Moreover, AC-IO-Ova NPs might assist the efficiency of anticancer cells, inducing an innate immune response via M1 macrophage polarization. We provide a novel synergistic chemoimmunotherapeutic strategy to enhance the anticancer efficacy of cisplatin via a chemotherapeutic agent 4.5GDP-Cis-pt NC and induce proinflammatory cytokines stimulating innate immunity through AC-IO-Ova NPs against tumors.

Microporous polymers with cascaded cavities for controlled transport of small gas molecules.

In membrane-based separation, molecular size differences relative to membrane pore sizes govern mass flux and separation efficiency. In applications requiring complex molecular differentiation, such as in natural gas processing, cascaded pore size distributions in membranes allow different permeate molecules to be separated without a reduction in throughput. Here, we report the decoration of microporous polymer membrane surfaces with molecular fluorine. Molecular fluorine penetrates through the microporous interface and reacts with rigid polymeric backbones, resulting in membrane micropores with multimodal pore size distributions. The fluorine acts as angstrom-scale apertures that can be controlled for molecular transport. We achieved a highly effective gas separation performance in several industrially relevant hollow-fibrous modular platform with stable responses over 1 year.

Hydrogen Bond Strength-Mediated Self-Assembly of Supramolecular Nanogels for Selective and Effective Cancer Treatment.

This study provides a significant contribution to the development of multiple hydrogen-bonded supramolecular nanocarrier systems by demonstrating that controlling the hydrogen bond strength within supramolecular polymers represents a crucial factor to tailor the drug delivery performance and enhance the effectiveness of cancer therapy. Herein, we successfully developed two kinds of poly(ethylene glycol)-based telechelic polymers Cy-PEG and UrCy-PEG having self-constituted double and quadruple hydrogen-bonding cytosine (Cy) and ureido-cytosine (UrCy) end-capped groups, respectively, which directly assemble into spherical nanogels with a number of interesting physical characteristics in aqueous solutions. The UrCy-PEG nanogels containing quadruple hydrogen-bonded UrCy dimers exhibited excellent long-term structural stability in a serum-containing biological medium, whereas the double hydrogen-bonded Cy moieties could not maintain the structural integrity of the Cy-PEG nanogels. More importantly, after the drug encapsulation process, a series of in vitro experiments clearly confirmed that drug-loaded UrCy-PEG nanogels induced selective apoptotic cell death in cancer cells without causing significant cytotoxicity to healthy cells, while drug-loaded Cy-PEG nanogels exerted nonselective cytotoxicity toward both cancer and normal cells, indicating that increasing the strength of hydrogen bonds in nanogels plays a key role in enhancing the selective cellular uptake and cytotoxicity of drugs and the subsequent induction of apoptosis in cancer cells.

Preparation of physically crosslinked polyelectrolyte Gelatin-Tannic acid-κ-Carrageenan (GTC) microparticles as hemostatic agents.

In humans, excessive bleeding during civilian accidents, and surgery account for 40% of the mortality worldwide. Hence, the development of biocompatible hemostatic materials useful for rapid hemorrhage control has become a fundamental research problem in the biomedicine community. In this study, we prepared biocompatible gelatin-tannic acid-κ-carrageenan (GTC) microparticles using a facile Tween 80 stabilized water-in-oil (W/O) emulsion method for rapid hemostasis. The formation of GTC microparticles occurs via polyelectrolyte interactions between gelatin and k-carrageenan as well as hydrogen bonding from tannic acid. In addition, the GTC microparticles formulated in our study showed high water adsorption ability with a low volume-swelling ratio for a particle size of 46 µm. In addition, the GTC microparticles displayed >80% biocompatibility in NIH 3T3 cells and <5% hemocompatibility in hemolysis ratio tests. Notably, the GTC microparticles induced rapid blood clotting in 50 s and blood loss of approximately 46 mg in the femoral artery of BALB/c female mice with a 100% survival rate that was significantly better than the control group (blood clot time:250 s; blood loss: 259 mg). Thus, the findings from our study collectively suggest that GTC microparticles may play a promising clinical role in medical applications to tackle hemorrhage control.

Synthesis of hierarchically porous 3D polymeric carbon superstructures with nitrogen-doping by self-transformation: a robust electrocatalyst for the detection of herbicide bentazone.

Bentazone (BEZ) is one of the utmost selective problematic contact-past herbicide with high toxicity for humans owing to feasible contamination of surface and ground water. In this work, an electrochemical sensor has been developed for the sensitive detection of BEZ, based on hierarchically porous three-dimensional (3D) carbon superstructures (CS)-modified electrodes. The CSs (namely, CSHEX, CSPY, CSACN, and CSNOS) were prepared by the pyrolysis process from organic porous polyacrylonitrile (PAN) superstructure particles (namely, PANHEX, PANPY, PANACN, and PANNOS) obtained by free radical polymerization method using different solvents (hexane, pyridine, acetonitrile, and also no solvent). The assembly with the working electrode of CSs causes the electrocatalytic BEZ oxidation by rapid electron transfer compared to the PAN superstructures and bare electrodes. Intriguingly, compared to all electrodes, CSHEX-modified electrode showed the superior electrochemical detection of BEZ at a working potential of 0.99 V (vs. Ag/AgCl), very low detection limit (0.002 µM), wide dynamic linear range (0.03 to 200 µM), high sensitivity (9.95 µA µM-1 cm-2), and excellent reliability. The advanced sensors displayed an intensification of oxidation peak current of BEZ with high selectivity, remarkable sensitivity, and reproducibility for BEZ detection and received satisfactory outcomes designating the application of sensors for the determination of BEZ in river water samples.

Preparation of thermosensitive PNIPAm-based copolymer coated cytodex 3 microcarriers for efficient nonenzymatic cell harvesting during 3D culturing.

Enzymatic detachment of cells might damage important features and functions of cells and could affect subsequent cell-based applications. Therefore, nonenzymatic cell detachment using thermosensitive polymer matrix is necessary for maintaining cell quality after harvesting. In this study, we prepared thermosensitive PNIPAm-co-AAc-b-PS and PNIPAm-co-AAm-b-PS copolymers and low critical solution temperature (LCST) was tuned near to body temperature. Then, spin coated polymer films were prepared for cell adhesion and thermal-induced cell detachment. The alpha-step analysis and scanning electron microscope image of the films suggested that the thickness of the films depends on the molecular weight and concentration which ranged from 206 to 1330 nm for PNIPAm-co-AAc-b-PS and 97.5-497 nm for PNIPAm-co-AAm-b-PS. The contact angles of the films verified that the polymer surface was moderately hydrophilic at 37°C. Importantly, RAW264.7 cells were convincingly proliferated on the films to a confluent of >80% within 48 h and abled to detach by reducing the temperature. However, relatively more cells were grown on PNIPAm-co-AAm-b-PS (5%w/v) films and thermal-induced cell detachment was more abundant in this formulation. As a result, PNIPAm-co-AAm-b-PS (5%w/v) was further used to coat commercial cytodex 3 microcarriers for 3D cell culturing and interestingly enhanced cell detachment with preserved potential of recovery was observed at a temperature of below LCST. Thus, surface modification of microcarriers with thermosensitive PNIPAm-co-AAm-b-PS could be vital strategy for nonenzymatic cell detachment and to achieve adequate number of cells with maximum cell viability and functionality.

Enhanced Cellular Uptake in an Electrostatically Interacting Fucoidan-L-Arginine Fiber Complex.

Fucoidan is an abundant marine sulfated polysaccharide extracted from the cell wall of brown macroalgae (seaweed). Recently, fucoidan has been highly involved in various industrial applications, such as pharmaceuticals, biomedicals, cosmetics, and food. However, the presence of a sulfate group (negative surface charge) in the fucoidan structure limits its potential and biological activity for use in biomedical applications during cellular uptake. Thus, we aimed to improve the uptake of fucoidan by using an L-arginine uptake enhancer within an in vitro study. A Fucoidan-L-Arginine (Fuc-L-Arg) fiber complex was prepared via α-helical electrostatic interactions using a freeze-drying technique and confirmed using field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. In addition, fucoidan was conjugated with cyanine 3 (Cy3) dye to track its cellular uptake. Furthermore, the results of Fuc-L-Arg (1:1, 1:2.5) complexes revealed biocompatibility >80% at various concentrations (5, 10, 25, 50, 100 µg/mL). Owing to the higher internalization of the Fuc-L-Arg (1:5) complex, it exhibited <80% biocompatibility at higher concentrations (25, 50, 100 µg/mL) of the complex. In addition, improved cellular internalization of Fuc-L-Arg complexes (1:5) in HeLa cells have been proved via flow cytometry quantitative analysis. Hence, we highlight that the Fuc-L-Arg (1:5) fiber complex can act as an excellent biocomplex to exhibit potential bioactivities, such as targeting cancers, as fucoidan shows higher permeability in HeLa cells.

Investigation of dual plasmonic core-shell Ag@CuS nanoparticles for potential surface-enhanced Raman spectroscopy-guided photothermal therapy.

Aim: To prepare efficient metal-semiconductor nanoparticles as noninvasive, real-time imaging probes for photothermal therapy (PTT) applications. Materials & methods: A bottom-up approach was used to fabricate core-shell Ag@CuS nanoparticles (NPs). PTT and Raman mapping were done using HeLa cells. Theoretical simulation of electric field enhancement and heat dissipation density of Ag@CuS NPs was performed. Results: PTT-induced hyperthermia was achieved under 940 nm near-infrared light irradiation. Surface-enhanced Raman spectroscopy (SERS) signals of dye molecules were observed when conjugated with Ag@CuS NPs. Conclusion: Ag@CuS NPs are found to be efficient for SERS imaging and localized heating under laser irradiation, making a promising candidate for SERS-guided PTT.